Walter Houser Brattain (/ˈbrætən/; February 10, 1902 – October 13, 1987) was an American physicist who shared the 1956 Nobel Prize in Physics with John Bardeen and William Shockley for their invention of the point-contact transistor.

[8] Brattain and his classmates Walker Bleakney, Vladimir Rojansky and E. John Workman would all go on to have distinguished careers, later becoming known as "the four horsemen of physics".

His thesis, supervised by John T. Tate, was Efficiency of Excitation by Electron Impact and Anomalous Scattering in Mercury Vapor.

[2] At the time, the telephone industry was heavily dependent on the use of vacuum tubes to control electron flow and amplify current.

[15] In 1945, Bell Labs reorganized and created a group specifically to do fundamental research in solid state physics, relating to communications technologies.

[3]: 77  Bardeen was a quantum physicist, Brattain a gifted experimenter in materials science, and Shockley, the leader of their team, was an expert in solid-state physics.

[16] According to theories of the time, Shockley's field effect transistor, a cylinder coated thinly with silicon and mounted close to a metal plate, should have worked.

[18]: 467–468  Brattain and Bardeen eventually managed to create a small level of amplification by pushing a gold metal point into the silicon, and surrounding it with distilled water.

"[18]: 470 On December 23, 1947, Walter Brattain, John Bardeen, and William B. Shockley demonstrated the first working transistor to their colleagues at Bell Laboratories.

Amplifying small electrical signals and supporting the processing of digital information, the transistor is "the key enabler of modern electronics".

"[8] Convinced by the 1947 demonstration that a major breakthrough was being made, Bell Laboratories focused intensively on what it now called the Surface States Project.

Carefully restricted internal conferences within Bell Labs shared information about the work of Brattain, Bardeen, Shockley and others who were engaged in related research.

[20] There was considerable anxiety over whether Ralph Bray and Seymour Benzer, studying resistance in germanium at Purdue University, might make a similar discovery and publish before Bell Laboratories.

Bell Laboratories organized several symposia, open to university, industry and military participants, which were attended by hundreds of scientists in September 1951, April 1952, and 1956.

[20] Shockley's theory of the junction transistor was an "impressive achievement", pointing the way to future solid-state electronics, but it would be several years before its construction would become practically possible.

[3]: 79–81 [24] Describing it as "an intolerable situation", Bardeen left Bell Laboratories in 1951 to go to the University of Illinois, where he eventually won a second Nobel Prize for his theory of superconductivity.

[23][25] In 1956, the three men were jointly awarded the Nobel Prize in Physics by King Gustaf VI Adolf of Sweden "for research on semiconductors and the discovery of the transistor effect.

He also collaborated with Whitman chemistry professor David Frasco, using phospholipid bilayers as a model to study the surface of living cells and their absorption processes.

[8] At Whitman, the Walter Brattain Scholarships are awarded on a merit basis to "entering students who have achieved high academic excellence in their college preparatory work."